In an X-ray apparatus e.g. comprising an X-ray generator, high voltage supply is required for operation of an X-ray tube. The generated high voltage is usually measured with a high voltage component such as, for example, a high voltage resistor divider (bleeder), which also performs an additional function of discharging the capacitors used in a voltage multiplier.
For example, high voltage resistor dividers have usually a substantially long structure to ensure sufficient insulation on its surface. Such a configuration comprising a long structure with high voltage at one end and a near ground electrical potential at the other end is more likely to create a non-uniform electric field distribution along the length of the high voltage resistor divider. Furthermore, the electric field gets distorted depending upon the neighboring components and their electrical potential.
Both the above-mentioned aspects are understood in lumped model as varying distribution of capacitors along the length of the high voltage resistor divider. Thus, the non-uniform distribution of electrical potential along the length of the high voltage divider resistor and the stray capacitance variation depending on neighborhood affects the divider ratio, response and accuracy of measurement.
A known method of grading and shielding a high voltage component such as, for example, a high voltage resistor divider includes arranging the resistor in-between at least a pair of parallel plates that acts as a shield and at the same time provide a linear voltage distribution. However, this arrangement requires use of a special package. Also, the resistor arrangement has a significant capacitance arising due to the parallel plates. Although the capacitance is compensated at the low voltage end, the response (bandwidth) of the divider system becomes low, thereby making the divider limited for measuring fast transients. Further, for compact configuration requirements, a separate arrangement for the high voltage resistor divider is more likely to consume more space and also become expensive.
Thus, the above-mentioned method does not provide a configuration to build a high voltage component e.g. a high voltage divider that is compact. A very compact arrangement can result from mounting the divider in the PCB used for high voltage generation, for example, a multiplier PCB in an X-ray apparatus.